Insulation degradation monitoring device

Abstract

An insulation degradation monitoring device by which a degradation state of an insulator can be constantly monitored by a simple configuration, and a degradation degree can be decided. An insulation degradation monitoring device for an insulator, by which a high-voltage charging portion of an electric instrument is insulated from and supported to a grounding metal component, includes a penetration-type electric current sensor which is inserted to a connecting portion of the insulator and the grounding metal component, and detects a leakage electric current which is passed from the high-voltage charging portion through the insulator and is flowed to the grounding metal component; and a decision means which is connected to an output side of the electric current sensor, and decides a degradation degree of the insulator in accordance with a value of the leakage electric current.

What is claimed is: 
     
       1. An insulation degradation monitoring device for an insulator, by which a high-voltage charging portion of an electric instrument is insulated from and supported to a grounding metal component, comprising:
 an electric current sensor having an annular shape which is inserted to a connecting portion of the insulator and the grounding metal component, and detects a leakage electric current which is passed from the high-voltage charging portion through the insulator and is flowed to the grounding metal component; and 
 a controller connected to an output side of the electric current sensor, and decides a degradation degree of the insulator in accordance with a value of the leakage electric current; wherein 
 a buried metal having a screw hole for attaching is provided at an end portion of the insulator on the grounding metal component side, and at an end of the buried metal facing to the grounding metal component, a protruded portion which is protruded with a slightly longer length than a thickness of the electric current sensor, from an end surface of the insulator, is formed, and the protruded portion is configured in such a way that the outside shape of the protruded portion is smaller than an inner diameter of the electric current sensor, 
 and the electric current sensor is arranged between the insulator and the grounding metal component in a state where the electric current sensor is fitted to the protruded portion of the buried metal. 
 
     
     
       2. The insulation degradation monitoring device as recited in  claim 1 , wherein a plurality of pleats are provided at an outer circumferential portion of the electric current sensor. 
     
     
       3. The insulation degradation monitoring device as recited in  claim 2 , wherein
 a conductive sleeve having a cylindrical shape is inserted to an inner circumference side of the electric current sensor, and one end portion of the conductive sleeve is contacted to the insulator, and the other end portion of the conductive sleeve is contacted to the grounding metal component. 
 
     
     
       4. The insulation degradation monitoring device as recited in  claim 1 , wherein
 a conductive sleeve having a cylindrical shape is inserted to an inner circumference side of the electric current sensor, and one end portion of the conductive sleeve is contacted to the insulator, and the other end portion of the conductive sleeve is contacted to the grounding metal component. 
 
     
     
       5. The insulation degradation monitoring device as recited in  claim 1 , wherein
 the insulator and the grounding metal component are connected at a plurality of portions, and the insulator and the grounding metal component include a plurality of connecting portions, and 
 the electric current sensor is provided at each of the plurality of connecting portions, and 
 a value of the leakage electric current, which is detected at the plurality of connecting portions, is integrated at the controller, and a degradation degree of the insulator is decided in accordance with the value of the integrated leakage electric current. 
 
     
     
       6. An insulation degradation monitoring device for an insulator, by which a high-voltage charging portion of an electric instrument is insulated from and supported to a grounding metal component, comprising:
 an electric current sensor which is inserted to a connecting portion of the insulator and the grounding metal component, and detects a leakage electric current which is passed from the high-voltage charging portion through the insulator and is flowed to the grounding metal component; and 
 a controller connected to an output side of the electric current sensor, and decides a degradation degree of the insulator in accordance with a value of the leakage electric current; wherein 
 a plurality of pleats are provided at an outer circumferential portion of the electric current sensor. 
 
     
     
       7. The insulation degradation monitoring device as recited in  claim 6 , wherein
 the insulator and the grounding metal component are connected at a plurality of portions, and the insulator and the grounding metal component include a plurality of connecting portions, and 
 the electric current sensor is provided at each of the plurality of connecting portions, and 
 a value of the leakage electric current, which is detected at the plurality of connecting portions, is integrated at the controller, and a degradation degree of the insulator is decided in accordance with the value of the integrated leakage electric current.